Thermostatically controlled mixing valve



April 24, 51 w. c. KIRK ET AL THERMOSTATICALLY CONTROLLED MIXING VALVE 2 Sheets-Sheet 1 Filed June 25, 1946 April 24, 1951 w. c. KIRK ET AL THERMOSTATICALLY CONTROLLED MIXING VALVE 2 Sheets-Sheet 2 Filgd June 25, 1946 Patented Apr. 24, 1951 UNITED STATES PATENT OFFICE THERMOSTATICALLY CONTROLLED MIXING VALVE Wayne 0. Kirk, South Bend, Ind and Malcolm K. Parkhurst, New York, N. Y.; said Kirk assignor to Lyndon W. Burch, New York, N. Y.

Application June 25, 1946, Serial No. 679,088

2 Claims. 1

' perature as high as 150 F. Accordingly, it is desirable that the operator be ableto change the setting of the mixing valve so as to give a water mixture having either of these temperatures, and it is highly advantageous that the setting of the valve be shiftable from a remote point.

In addition, many housewives desire to be able to adjust particularly the upper of these temperatures.

In order to meet these requirements a valve in accordance with our invention is provided with an electro-magnet for shifting the setting of the valve from the low to the high temperature value, which magnet may be controlled at any remote point by means of an electric switch.

In addition, the higher temperature value may be adjusted by rotating a shaft, as by means of a knob secured thereto. Provision is also made for adjusting the lower temperature value, but inasmuch as this value in practice seldom needs to be adjusted by the operator, the means for making the adjustment preferably is not accessible from the operating panel of the washing machine.

Further objects and advantages of our invention will be apparent from the following description considered in connection with the accompanying drawings, which form a part of this specification, and of which:

Fig. 1 is a top view of a mixing valve in accordance with our invention;

Fig. 2 is a cross sectional view on an enlarged scale, taken on the line 2-2 of Fig. 1;

Fig. 3 is a cross-sectional view on a reduced scale, taken on the line 3-3 of Fig. 2; and

Fig. ,4 is a cross-sectional view on an enlarged scale, taken on the line 4-4 of Fig. 3.

Referring to the drawings, reference character While the inlet port I4 is connected to a source of hot water under pressure, normally the cold and 7 hot water lines of a domestic plumbing system. The outlet port I 6 is connected-by a suitable conduit to the cylinder of the washing machine for conducting thereto the mixture formed in the mixing chamber l1.

Inlet port I2 communicates with the housing between valve seats l8 and 20, while inlet port I 4 communicates with the housing between valve seats 22 and 24. A pair of balanced valves 26 and 28 are arranged to cooperate with the respective pairs of seats. These valves are springloaded by means of helical springs 30 and 32, respectively, which bias the valves towards closed position. The stems of the valves are hollow so that water passing the seats l8 and 22 may flow through the hollow stems to the mixing chamber I! of the valve housing. Members 34 and 3B,

which may have the general shape of hair pins, are secured within the hollow stems of the two valves and abut against, opposite sides of the free end of a bimetallic element 38. The major portion of this element is in the form of a spiral with the inner end thereof secured to a shaft which is turnably mounted within the housing Ill. The strip of metal on the inner side of the bimetallicelement has a higher coefficient of expansion than the strip on the outer side. Consequently, upon an increase in temperature the inner strip expands more than the outer, thus causing the spiral to unwind which in turn causes the free ends of the bimetallic element to move to the left, as viewed in Fig. 2, so as to simultaneously increase the opening through the valve 26 and decrease the opening through the valve 28.

The parts are so proportioned that both of these valves may be fully open or fully closed at the same time andwhen one valve is fully opened the other is fully closed.

Rigidlysecured to the shaft 40 is one arm 42 which is biased ina clockwise direction, as viewed in Fig. 2, by the tension spring 44. Movement of the arm 42 in a clockwise direction is limited by means of a bolt 46 which is threaded through the casing I [land is provided with a suitable packing 48 for preventing leakage of water. Secured to the arm 42 near the free end thereof is a pin 5!] arranged to move up and down in slots 52 formed in the legs of a forkedmember 54. The member 54 has threaded engagement with a shaft 56 which is rotatably mounted in a. bushing 58 carried by the housing I 0. Any suitable means may be provided for preventing the leakage of water out of the housing along the shaft 56, and as shown the shaft is provided with a conical surface 6B which cooperates with a similar surface formed in the bushing. In addition, packing glands 62 are provided on the shaft and the two conical surfaces are maintained in engagement by means of a coil spring 64 compressed between the bushing 58 and a clamp 66 which is removably secured to thejsh'aft by means ,of a setscrew fit. A knob Hi is secured to the shaft for the purpose of turning it.

As seen more particularly in Fig. 3, a tubular sleeve 12 made of copper or 'other suitablenonmagnetic material is secured to an opening inithe housing In by means of a nut. An armature 16, having an outer surface which .is preferably hexagonal or of other non-.circulanshape isreciprocably mounted in the tubular member 12 and is connected at its lower end to the pin 50 by means of a spring 18. The non-circularshape of the armature is preferable in order to prevent water from becoming trapped in the upper end ofthe tube '12 and thus interfering with reciprocation of the armature. ranged around-the exterior-of the tubular :mernber 12 and is'connected by means of leads ttwith any suitable source of electric currentya switch A solenoid. coil 80 isar- 84 being interposed in the circuit.

The above described device operates ,asfollows: If it is desired that the temperature of the watermixture leaving the valve through the outlet l6 be at the lower value, namely in the neigh- -borhoo d of 100 F.,"the switch 84 is left open, -=whereupon spring '44 holds, the arm 42 in its lower 'limit-position-against ,the' upper end of the adjusting screw 45. With the shaft 40 and hence "the innerendofflthebimetallic element in the position determined bythis position of the arm 42, the bimetallic element will so regulate the positions of thevalves 25 and 28 that the mixture of --the cold and hot water emitted from these valves and flowing in contact with the element in the -'mixing chamber-l7 will bemaintained at the desired lower temperature of about 100 F. If the temperature of the mixture tends to go'above this value, the bimetallic element will immediately uncoil slightly so as to further open the valve' 26 and further'close the valve-2'3, thus, increasing the proportion of the cold water ad- -mittedto the mixing "chamber.

If'itis desired tovary or adjust the value of the perature.

YWhen it-is desiredto change the'setting of the "valve so thatthe latter-will maintain the higher temperature, the switch 84 is closed. This ener- "gizes the solenoid coil 80, thus causing it to draw the armature '15 upwardly within the tube '12.

j Inasmuch-as'the lower end of the armature is connected to the pin '58 carried by the arm 42, -this turnsthearm in a counter-clockwise direc- :ltion, as viewed in Fig. 2-, 'untilthe pin 56 strikes the ends of the slots52 in'the forked member 54.

" This in turn pivots theshaft 40 so as to cause thebimetallic'element to increase the opening of the hot water valve 28 and to decrease the opening of the cold water valve 26. Under these condi- ':?tions the bimetallicielement will maintain the .ztwo valves 'in the proper-- position so that the 4 water mixture is maintained at the higher temperature.

Inasmuch as the position of the'ends of the slots 52 determines the position of the arm 42 when the solenoid is energized, the upper value of the temperature maintained by the valve may be adjustedb'y raising or lowering the forked "member 54. This in turn may be accomplished by rotating the shaft 56 so as to cause the forked .10;

member to advance either upwardly or downwardly 011113116 threaded portion of the shaft. :Raising the forked member increases the value of the higher temperature, while lowering this member decreases the value.

From the foregoing description it will be seen that the values of the upper and lower tempera- I: tures may beadjusted independently of each other from the exteriorof the valve housing and without in any manner disassembling the valve. Furthermore, theshift from thelow to the high either of these values, and theshifting may be made at' any; remote point by merely closing, or

opening the electric switch.

Due to the fact that'the adjustment of'the lower temperatur-eis usually made only, at lthe factory, and need notbe made by thef'operator, a simple bolt 46 has beenshown 'as employed for this purpose. However, if it is desirable 'to'have this adjustment-easily-mjade'by the operator,

'- an arrangementsimilar to that including the I shaft 56-could be substituted for the bolt Mi.

Due to the balancing of boththeQhot-andpold water valves; the mixing valveis unaffected by variations in the pressure of the water supplied thereto or by variations-in the; pressure ofithe hot water with respect to'that ofthe cold water.

While we have shown one-more or less specific embodiment of'o'ur inventiongit is to be understood that this has been done for purpose ofillustration only and that the scope of our invention is not'to be limited thereby but is "to be determined from the appended claims.

What is claimed: V

' 1. 'In' a mixing valve, a housing having .hOti-and" cold water inlet ports and anoutlet'port; a pair of balanced valve-members movably arranged in I said housing and disposed in the r-espe'ctive paths of'flow between said inletports and said, outlet port, a shaft turnably mounted and; enclosed within said housing; a bimetallic element having one end secured to said shaftand the other end connected to simultaneously adjust the positions of said valves, anarm withinsaid housin .secured to said shaft; abutment means for limiting the turning of ,said shaft in botlfdirections,

*one of said abutment meansincluding a threaded 'member; a shaft rotatably mounted in and extending through {said housi andjghaving threaded engagement with the abutmentmember, whereby rotation of the last-mentioned shaft changes the position ofgsa'id abutment. member, and means-operable fromjthe exterior of said housing for turning said arm from contact, with one of said abutment means to contactwith the other abutment means. s

' 2. 'In a miiring valve, a housing having hot and cold water inlet ports. and. an outlet port, a pair of-b-alanced valve members, movably arranged in said housing;and disposed in the respective paths of flow between said inlet ports and said'outlet port, a shaft turnably mounted and enclosed within said housing, 'a bimetallic.element.having one-end securedtosaid shaft and the other end ergization of said solenoid to move said arm into contact with one of said abutment means, spring means biasing said arm towards the other abutment means, one of said abutment means including a threaded member, and a shaft rotatably mounted in and extending through said member and having threaded engagement with the abutment member, whereby rotation of the last-mentioned member from the exterior of said housing changes the position 01' said abutment member.

WAYNE C. KIRK. MALCOLM K. PARKHURST.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS.

Number Name Date 1,597,773 Dodge Aug. 31, 1926 1,787,304 Becker Dec. 30, 1930 1,932,148 Schneider Oct. 24, 1933 2,064,053 Balzer Dec. 15, 1936 2,287,810 Lund June 30, 1942 2,296,266 Breckenridge Sept. 22, 1942 2,448,170 Brown Aug. 31, 1948 

